So In planning out my hikes next year, I've hit an impasse about Memorial Day weekend.

I did the north rim this year from Big Oak Flat Rd, so as far as the valley trails goes, that leaves either starting at Tunnel View and doing the south rim (staying at Dewey Point the first night and then a long hike to get somewhere else I can camp) or Snow Creek to Tenya Lake and down to Clouds Rest and Half Dome. But I plan on doing a bigger loop from Tuolumne Meadows that includes Half Dome/Clouds Rest later in the year.

So as far as late spring hikes in a normal snow year, how does Hetch Hechy usually melt out to give some backpacking trips from there?

I guess I could look at some hikes starting around Wawona as well.

Any other spring backpacking hikes I'm missing in Yosemite?

Of course, if we get a dumping like this last year... all bets are off (although that doesn't seem likely so far).

Yeah, it is really going to depend on how much melt there ends up being.

Out of Hetch Hetchy, you'll first have the falls, which may end up being impassible because of the runoff. Then you'll inevitably end up with flooding in the valleys up higher that can end up anywhere from knee to waist deep, on top of mosquitoes. If and when you get up to Frog Creek, assuming it doesn't just kill you if you decide that you're going to try to ford it, it'll probably at least end your trip and turn you around right then and there, even under the best of conditions.

Out of Wawana, Chilnualna Creek is going to also likely be impassible that early on, even in a relatively mild winter.

You can have all the gear and knowhow you can use, but that high water and going solo in your case are going to really work against you in a big way.

It all depends on weather and snowpack. We've done Hetch-hetchy up past Rancheria Falls to LeConte point over Easter, and it was a cakewalk. But as Phil says, the higher you go, the more snow you are going to find. And if it's a warm weekend, the run-off will be something between impressive and terrifying for any of the creeks that don't have bridges. The bridge at Wapama Falls is regularly closed due to high water run-off in the spring. Wawona above Chilnualna Falls is certainly in that category as well, as is Bridalveil Campground to the area around Buena Vista Crest

For early season hikes, we've had pretty good luck tackling USFS roads that are closed. You can find a lot of these in the Stanislaus National Forest just north of Yosemite, and they usually offer a reasonably alternative--at least for quite a few miles. Look at Herring Creek Road, Eagle Meadows, etc.